The bald eagles that were found nesting at Mashomack in early March have evidently been taking parenting courses. It has been confirmed that two eaglets have been born.
The young birds are estimated at just over one month. Like osprey, the bald eagle’s incubation period is about 35 days. Unlike the osprey, eagles are on eggs in March, when osprey are normally just returning from their migration and beginning courtship.
Mike Scheibel, Mashomack’s natural resources manager, has been keeping a sharp (dare I say eagle?) eye on the nest, while carefully minimizing disturbance of the often sensitive birds. The nest is in a remote area, barely visible even to the trained eye. With trees leafing out, it will be lost to sight.
Mr. Scheibel reported, “On April 9, there did appear to be young in the nest, based primarily on the adults’ behavior … On April 21, I was able to confirm the presence of one young in the nest, with twins confirmed May 5.” On May 8, the New York State eagle expert estimated the babies were three and a half to four weeks old; they will be seven weeks old by the end of May.
The eaglets will remain in the nest for about three months; at that time they will have attained their full adult size and will take their first flight, an important milestone in the life of a young eagle known as “fledging.”
These are the first bald eagles on record to be born on Shelter Island. The Nature Conservancy will continue to protect and monitor the birds throughout the season to document their growth and development.
Dr. Bill Zitek is our lead volunteer for the Nestbox project and, working under Mike Scheibel, is also a bird bander. As part of the monitoring protocol, he fits the young nestlings (usually when they are about 12 days old) with bands that identify the individual (the metal numbered bands) and their age (the yellow plastic bands). He tagged the 2013 fledglings with red bands, and we’ve actually seen a few of them around this year. The colored bands allow us to know their age without having to capture them.
This past winter, Jim Colligan photographed a red-banded bird, showing that young birds don’t necessarily head south for the winter. We also had two red-banded birds nesting as a pair this year. Most likely they are not siblings, since we banded all 2013 birds with red, but both year-old birds have showed area fidelity.